Evolution in lesion index durability using the new third generation laser balloon catheter for pulmonary vein isolation – does the mechanical innovation mean also clinical innovation?

Background The new second- and third-generation endoscopic ablation systems (EAS 2 and EAS 3) have been launched in recent years. We aimed to assess the index lesion durability as well as gap localization using the multigenerational novel technologies in patients with recurrent atrial fibrillation (AF). Methods Consecutive patients who underwent the second ablation for recurrent AF following the initial pulmonary vein isolation (PVI) with EAS 2 or EAS 3 were investigated. The persistent durability of PVI and gap localization at the second procedure were analyzed using spiral mapping catheter and three-dimensional mapping system. Results A total of 34 patients (EAS3: N=13, 50 PVs, EAS2: N=21, 82 PVs) were enrolled. Repeat procedure was performed mean 11.9±9.3 months after the initial procedure. Persistent durable isolation of all four PVs was recorded in 6 (46.2%) patients in EAS3 and 4 (19.1%) patients in EAS2 (P=0.130). Ninety-one out of 132 (68.9%) PVs were persistently isolated with a higher rate in EAS3 (EAS3: 82.0% vs. EAS2: 61.0%, P=0.0113). A total of 45 gaps were recorded in 41 PVs, of which right superior PV (RSPV) was the predominantly common reconnected vein (15 gaps in 14 PVs) irrespective of generation difference (EAS 3: 4 gaps in 3 PVs and EAS 2: 12 gaps in 11 PVs). Anterior-segment of RSPV was the most common gap distribution (EAS 3: 2 gaps and EAS 2: 6 gaps). Logistic multivariate regression analysis revealed high-dose (≥8.5W) only ablation as an independent predictor of durable PVI (adjusted OR: 3.70, 95% CI [1.408 - 10.003], P=0.008) Conclusion The multigenerational technical innovation resulted in a higher index lesion durability in EAS3 guided PVI in patients with recurrent AF. The specific gap patterns frequent at RSPV, especially at the anterior-superior segment, and the feasibility of high-dose ablation were confirmed in successor EASs. Funding Acknowledgement Type of funding sources: None.